At the end of your opening sentence where you refer to Herodotus, you conclude by saying - "I think we agree about that."
I replied, beginning by saying that I didn't agree and then pointed out to you that Rosellini ascribed the Khnum Khufu inscription to Chephren, assuming that the ram and jug glyphs must have been a hitherto undiscovered way of writing 'sn' or 'brother' to Suphis.
He knew from Herodotus' account that G1 did not belong to Chephren and so assumed that the glyphs must read, 'brother of Khufu'. He knew, again from Herodotus, that this "brother's" name in Greek was written as Chephren.
It really is that simple.
Corpuscles has since cited a passage from Vyse's journal where he explains that this is what Rosellini must have thought, and that he was wrong and that it is not attested as 'sn' anywhere else in the archaelogical record.
EDITED: to correct a typo
Edited 1 time(s). Last edit at 24-Feb-19 15:00 by eyeofhorus33.